xref: /openbmc/qemu/target/s390x/cpu.c (revision c51a3f5d)
1 /*
2  * QEMU S/390 CPU
3  *
4  * Copyright (c) 2009 Ulrich Hecht
5  * Copyright (c) 2011 Alexander Graf
6  * Copyright (c) 2012 SUSE LINUX Products GmbH
7  * Copyright (c) 2012 IBM Corp.
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, see <http://www.gnu.org/licenses/>.
21  */
22 
23 #include "qemu/osdep.h"
24 #include "qapi/error.h"
25 #include "cpu.h"
26 #include "internal.h"
27 #include "kvm_s390x.h"
28 #include "sysemu/kvm.h"
29 #include "sysemu/reset.h"
30 #include "qemu/timer.h"
31 #include "qemu/error-report.h"
32 #include "qemu/module.h"
33 #include "trace.h"
34 #include "qapi/visitor.h"
35 #include "qapi/qapi-types-machine.h"
36 #include "qapi/qapi-visit-run-state.h"
37 #include "sysemu/hw_accel.h"
38 #include "hw/qdev-properties.h"
39 #ifndef CONFIG_USER_ONLY
40 #include "hw/s390x/pv.h"
41 #include "hw/boards.h"
42 #include "sysemu/arch_init.h"
43 #include "sysemu/sysemu.h"
44 #include "sysemu/tcg.h"
45 #endif
46 #include "fpu/softfloat-helpers.h"
47 
48 #define CR0_RESET       0xE0UL
49 #define CR14_RESET      0xC2000000UL;
50 
51 static void s390_cpu_set_pc(CPUState *cs, vaddr value)
52 {
53     S390CPU *cpu = S390_CPU(cs);
54 
55     cpu->env.psw.addr = value;
56 }
57 
58 static bool s390_cpu_has_work(CPUState *cs)
59 {
60     S390CPU *cpu = S390_CPU(cs);
61 
62     /* STOPPED cpus can never wake up */
63     if (s390_cpu_get_state(cpu) != S390_CPU_STATE_LOAD &&
64         s390_cpu_get_state(cpu) != S390_CPU_STATE_OPERATING) {
65         return false;
66     }
67 
68     if (!(cs->interrupt_request & CPU_INTERRUPT_HARD)) {
69         return false;
70     }
71 
72     return s390_cpu_has_int(cpu);
73 }
74 
75 #if !defined(CONFIG_USER_ONLY)
76 /* S390CPUClass::load_normal() */
77 static void s390_cpu_load_normal(CPUState *s)
78 {
79     S390CPU *cpu = S390_CPU(s);
80     uint64_t spsw;
81 
82     if (!s390_is_pv()) {
83         spsw = ldq_phys(s->as, 0);
84         cpu->env.psw.mask = spsw & PSW_MASK_SHORT_CTRL;
85         /*
86          * Invert short psw indication, so SIE will report a specification
87          * exception if it was not set.
88          */
89         cpu->env.psw.mask ^= PSW_MASK_SHORTPSW;
90         cpu->env.psw.addr = spsw & PSW_MASK_SHORT_ADDR;
91     } else {
92         /*
93          * Firmware requires us to set the load state before we set
94          * the cpu to operating on protected guests.
95          */
96         s390_cpu_set_state(S390_CPU_STATE_LOAD, cpu);
97     }
98     s390_cpu_set_state(S390_CPU_STATE_OPERATING, cpu);
99 }
100 #endif
101 
102 /* S390CPUClass::reset() */
103 static void s390_cpu_reset(CPUState *s, cpu_reset_type type)
104 {
105     S390CPU *cpu = S390_CPU(s);
106     S390CPUClass *scc = S390_CPU_GET_CLASS(cpu);
107     CPUS390XState *env = &cpu->env;
108     DeviceState *dev = DEVICE(s);
109 
110     scc->parent_reset(dev);
111     cpu->env.sigp_order = 0;
112     s390_cpu_set_state(S390_CPU_STATE_STOPPED, cpu);
113 
114     switch (type) {
115     case S390_CPU_RESET_CLEAR:
116         memset(env, 0, offsetof(CPUS390XState, start_initial_reset_fields));
117         /* fall through */
118     case S390_CPU_RESET_INITIAL:
119         /* initial reset does not clear everything! */
120         memset(&env->start_initial_reset_fields, 0,
121                offsetof(CPUS390XState, start_normal_reset_fields) -
122                offsetof(CPUS390XState, start_initial_reset_fields));
123 
124         /* architectured initial value for Breaking-Event-Address register */
125         env->gbea = 1;
126 
127         /* architectured initial values for CR 0 and 14 */
128         env->cregs[0] = CR0_RESET;
129         env->cregs[14] = CR14_RESET;
130 
131 #if defined(CONFIG_USER_ONLY)
132         /* user mode should always be allowed to use the full FPU */
133         env->cregs[0] |= CR0_AFP;
134         if (s390_has_feat(S390_FEAT_VECTOR)) {
135             env->cregs[0] |= CR0_VECTOR;
136         }
137 #endif
138 
139         /* tininess for underflow is detected before rounding */
140         set_float_detect_tininess(float_tininess_before_rounding,
141                                   &env->fpu_status);
142        /* fall through */
143     case S390_CPU_RESET_NORMAL:
144         env->psw.mask &= ~PSW_MASK_RI;
145         memset(&env->start_normal_reset_fields, 0,
146                offsetof(CPUS390XState, end_reset_fields) -
147                offsetof(CPUS390XState, start_normal_reset_fields));
148 
149         env->pfault_token = -1UL;
150         env->bpbc = false;
151         break;
152     default:
153         g_assert_not_reached();
154     }
155 
156     /* Reset state inside the kernel that we cannot access yet from QEMU. */
157     if (kvm_enabled()) {
158         switch (type) {
159         case S390_CPU_RESET_CLEAR:
160             kvm_s390_reset_vcpu_clear(cpu);
161             break;
162         case S390_CPU_RESET_INITIAL:
163             kvm_s390_reset_vcpu_initial(cpu);
164             break;
165         case S390_CPU_RESET_NORMAL:
166             kvm_s390_reset_vcpu_normal(cpu);
167             break;
168         }
169     }
170 }
171 
172 #if !defined(CONFIG_USER_ONLY)
173 static void s390_cpu_machine_reset_cb(void *opaque)
174 {
175     S390CPU *cpu = opaque;
176 
177     run_on_cpu(CPU(cpu), s390_do_cpu_full_reset, RUN_ON_CPU_NULL);
178 }
179 #endif
180 
181 static void s390_cpu_disas_set_info(CPUState *cpu, disassemble_info *info)
182 {
183     info->mach = bfd_mach_s390_64;
184     info->print_insn = print_insn_s390;
185 }
186 
187 static void s390_cpu_realizefn(DeviceState *dev, Error **errp)
188 {
189     CPUState *cs = CPU(dev);
190     S390CPUClass *scc = S390_CPU_GET_CLASS(dev);
191 #if !defined(CONFIG_USER_ONLY)
192     S390CPU *cpu = S390_CPU(dev);
193 #endif
194     Error *err = NULL;
195 
196     /* the model has to be realized before qemu_init_vcpu() due to kvm */
197     s390_realize_cpu_model(cs, &err);
198     if (err) {
199         goto out;
200     }
201 
202 #if !defined(CONFIG_USER_ONLY)
203     MachineState *ms = MACHINE(qdev_get_machine());
204     unsigned int max_cpus = ms->smp.max_cpus;
205     if (cpu->env.core_id >= max_cpus) {
206         error_setg(&err, "Unable to add CPU with core-id: %" PRIu32
207                    ", maximum core-id: %d", cpu->env.core_id,
208                    max_cpus - 1);
209         goto out;
210     }
211 
212     if (cpu_exists(cpu->env.core_id)) {
213         error_setg(&err, "Unable to add CPU with core-id: %" PRIu32
214                    ", it already exists", cpu->env.core_id);
215         goto out;
216     }
217 
218     /* sync cs->cpu_index and env->core_id. The latter is needed for TCG. */
219     cs->cpu_index = cpu->env.core_id;
220 #endif
221 
222     cpu_exec_realizefn(cs, &err);
223     if (err != NULL) {
224         goto out;
225     }
226 
227 #if !defined(CONFIG_USER_ONLY)
228     qemu_register_reset(s390_cpu_machine_reset_cb, cpu);
229 #endif
230     s390_cpu_gdb_init(cs);
231     qemu_init_vcpu(cs);
232 
233     /*
234      * KVM requires the initial CPU reset ioctl to be executed on the target
235      * CPU thread. CPU hotplug under single-threaded TCG will not work with
236      * run_on_cpu(), as run_on_cpu() will not work properly if called while
237      * the main thread is already running but the CPU hasn't been realized.
238      */
239     if (kvm_enabled()) {
240         run_on_cpu(cs, s390_do_cpu_full_reset, RUN_ON_CPU_NULL);
241     } else {
242         cpu_reset(cs);
243     }
244 
245     scc->parent_realize(dev, &err);
246 out:
247     error_propagate(errp, err);
248 }
249 
250 #if !defined(CONFIG_USER_ONLY)
251 static GuestPanicInformation *s390_cpu_get_crash_info(CPUState *cs)
252 {
253     GuestPanicInformation *panic_info;
254     S390CPU *cpu = S390_CPU(cs);
255 
256     cpu_synchronize_state(cs);
257     panic_info = g_malloc0(sizeof(GuestPanicInformation));
258 
259     panic_info->type = GUEST_PANIC_INFORMATION_TYPE_S390;
260     panic_info->u.s390.core = cpu->env.core_id;
261     panic_info->u.s390.psw_mask = cpu->env.psw.mask;
262     panic_info->u.s390.psw_addr = cpu->env.psw.addr;
263     panic_info->u.s390.reason = cpu->env.crash_reason;
264 
265     return panic_info;
266 }
267 
268 static void s390_cpu_get_crash_info_qom(Object *obj, Visitor *v,
269                                         const char *name, void *opaque,
270                                         Error **errp)
271 {
272     CPUState *cs = CPU(obj);
273     GuestPanicInformation *panic_info;
274 
275     if (!cs->crash_occurred) {
276         error_setg(errp, "No crash occurred");
277         return;
278     }
279 
280     panic_info = s390_cpu_get_crash_info(cs);
281 
282     visit_type_GuestPanicInformation(v, "crash-information", &panic_info,
283                                      errp);
284     qapi_free_GuestPanicInformation(panic_info);
285 }
286 #endif
287 
288 static void s390_cpu_initfn(Object *obj)
289 {
290     CPUState *cs = CPU(obj);
291     S390CPU *cpu = S390_CPU(obj);
292 
293     cpu_set_cpustate_pointers(cpu);
294     cs->exception_index = EXCP_HLT;
295 #if !defined(CONFIG_USER_ONLY)
296     cs->start_powered_off = true;
297     object_property_add(obj, "crash-information", "GuestPanicInformation",
298                         s390_cpu_get_crash_info_qom, NULL, NULL, NULL);
299     cpu->env.tod_timer =
300         timer_new_ns(QEMU_CLOCK_VIRTUAL, s390x_tod_timer, cpu);
301     cpu->env.cpu_timer =
302         timer_new_ns(QEMU_CLOCK_VIRTUAL, s390x_cpu_timer, cpu);
303     s390_cpu_set_state(S390_CPU_STATE_STOPPED, cpu);
304 #endif
305     s390_cpu_model_register_props(obj);
306 }
307 
308 static void s390_cpu_finalize(Object *obj)
309 {
310 #if !defined(CONFIG_USER_ONLY)
311     S390CPU *cpu = S390_CPU(obj);
312 
313     qemu_unregister_reset(s390_cpu_machine_reset_cb, cpu);
314     g_free(cpu->irqstate);
315 #endif
316 }
317 
318 #if !defined(CONFIG_USER_ONLY)
319 static bool disabled_wait(CPUState *cpu)
320 {
321     return cpu->halted && !(S390_CPU(cpu)->env.psw.mask &
322                             (PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK));
323 }
324 
325 static unsigned s390_count_running_cpus(void)
326 {
327     CPUState *cpu;
328     int nr_running = 0;
329 
330     CPU_FOREACH(cpu) {
331         uint8_t state = S390_CPU(cpu)->env.cpu_state;
332         if (state == S390_CPU_STATE_OPERATING ||
333             state == S390_CPU_STATE_LOAD) {
334             if (!disabled_wait(cpu)) {
335                 nr_running++;
336             }
337         }
338     }
339 
340     return nr_running;
341 }
342 
343 unsigned int s390_cpu_halt(S390CPU *cpu)
344 {
345     CPUState *cs = CPU(cpu);
346     trace_cpu_halt(cs->cpu_index);
347 
348     if (!cs->halted) {
349         cs->halted = 1;
350         cs->exception_index = EXCP_HLT;
351     }
352 
353     return s390_count_running_cpus();
354 }
355 
356 void s390_cpu_unhalt(S390CPU *cpu)
357 {
358     CPUState *cs = CPU(cpu);
359     trace_cpu_unhalt(cs->cpu_index);
360 
361     if (cs->halted) {
362         cs->halted = 0;
363         cs->exception_index = -1;
364     }
365 }
366 
367 unsigned int s390_cpu_set_state(uint8_t cpu_state, S390CPU *cpu)
368  {
369     trace_cpu_set_state(CPU(cpu)->cpu_index, cpu_state);
370 
371     switch (cpu_state) {
372     case S390_CPU_STATE_STOPPED:
373     case S390_CPU_STATE_CHECK_STOP:
374         /* halt the cpu for common infrastructure */
375         s390_cpu_halt(cpu);
376         break;
377     case S390_CPU_STATE_OPERATING:
378     case S390_CPU_STATE_LOAD:
379         /*
380          * Starting a CPU with a PSW WAIT bit set:
381          * KVM: handles this internally and triggers another WAIT exit.
382          * TCG: will actually try to continue to run. Don't unhalt, will
383          *      be done when the CPU actually has work (an interrupt).
384          */
385         if (!tcg_enabled() || !(cpu->env.psw.mask & PSW_MASK_WAIT)) {
386             s390_cpu_unhalt(cpu);
387         }
388         break;
389     default:
390         error_report("Requested CPU state is not a valid S390 CPU state: %u",
391                      cpu_state);
392         exit(1);
393     }
394     if (kvm_enabled() && cpu->env.cpu_state != cpu_state) {
395         kvm_s390_set_cpu_state(cpu, cpu_state);
396     }
397     cpu->env.cpu_state = cpu_state;
398 
399     return s390_count_running_cpus();
400 }
401 
402 int s390_set_memory_limit(uint64_t new_limit, uint64_t *hw_limit)
403 {
404     if (kvm_enabled()) {
405         return kvm_s390_set_mem_limit(new_limit, hw_limit);
406     }
407     return 0;
408 }
409 
410 void s390_set_max_pagesize(uint64_t pagesize, Error **errp)
411 {
412     if (kvm_enabled()) {
413         kvm_s390_set_max_pagesize(pagesize, errp);
414     }
415 }
416 
417 void s390_cmma_reset(void)
418 {
419     if (kvm_enabled()) {
420         kvm_s390_cmma_reset();
421     }
422 }
423 
424 int s390_assign_subch_ioeventfd(EventNotifier *notifier, uint32_t sch_id,
425                                 int vq, bool assign)
426 {
427     if (kvm_enabled()) {
428         return kvm_s390_assign_subch_ioeventfd(notifier, sch_id, vq, assign);
429     } else {
430         return 0;
431     }
432 }
433 
434 void s390_crypto_reset(void)
435 {
436     if (kvm_enabled()) {
437         kvm_s390_crypto_reset();
438     }
439 }
440 
441 void s390_enable_css_support(S390CPU *cpu)
442 {
443     if (kvm_enabled()) {
444         kvm_s390_enable_css_support(cpu);
445     }
446 }
447 #endif
448 
449 static gchar *s390_gdb_arch_name(CPUState *cs)
450 {
451     return g_strdup("s390:64-bit");
452 }
453 
454 static Property s390x_cpu_properties[] = {
455 #if !defined(CONFIG_USER_ONLY)
456     DEFINE_PROP_UINT32("core-id", S390CPU, env.core_id, 0),
457 #endif
458     DEFINE_PROP_END_OF_LIST()
459 };
460 
461 static void s390_cpu_reset_full(DeviceState *dev)
462 {
463     CPUState *s = CPU(dev);
464     return s390_cpu_reset(s, S390_CPU_RESET_CLEAR);
465 }
466 
467 static void s390_cpu_class_init(ObjectClass *oc, void *data)
468 {
469     S390CPUClass *scc = S390_CPU_CLASS(oc);
470     CPUClass *cc = CPU_CLASS(scc);
471     DeviceClass *dc = DEVICE_CLASS(oc);
472 
473     device_class_set_parent_realize(dc, s390_cpu_realizefn,
474                                     &scc->parent_realize);
475     device_class_set_props(dc, s390x_cpu_properties);
476     dc->user_creatable = true;
477 
478     device_class_set_parent_reset(dc, s390_cpu_reset_full, &scc->parent_reset);
479 #if !defined(CONFIG_USER_ONLY)
480     scc->load_normal = s390_cpu_load_normal;
481 #endif
482     scc->reset = s390_cpu_reset;
483     cc->class_by_name = s390_cpu_class_by_name,
484     cc->has_work = s390_cpu_has_work;
485 #ifdef CONFIG_TCG
486     cc->do_interrupt = s390_cpu_do_interrupt;
487 #endif
488     cc->dump_state = s390_cpu_dump_state;
489     cc->set_pc = s390_cpu_set_pc;
490     cc->gdb_read_register = s390_cpu_gdb_read_register;
491     cc->gdb_write_register = s390_cpu_gdb_write_register;
492 #ifndef CONFIG_USER_ONLY
493     cc->get_phys_page_debug = s390_cpu_get_phys_page_debug;
494     cc->vmsd = &vmstate_s390_cpu;
495     cc->get_crash_info = s390_cpu_get_crash_info;
496     cc->write_elf64_note = s390_cpu_write_elf64_note;
497 #ifdef CONFIG_TCG
498     cc->cpu_exec_interrupt = s390_cpu_exec_interrupt;
499     cc->debug_excp_handler = s390x_cpu_debug_excp_handler;
500     cc->do_unaligned_access = s390x_cpu_do_unaligned_access;
501 #endif
502 #endif
503     cc->disas_set_info = s390_cpu_disas_set_info;
504 #ifdef CONFIG_TCG
505     cc->tcg_initialize = s390x_translate_init;
506     cc->tlb_fill = s390_cpu_tlb_fill;
507 #endif
508 
509     cc->gdb_num_core_regs = S390_NUM_CORE_REGS;
510     cc->gdb_core_xml_file = "s390x-core64.xml";
511     cc->gdb_arch_name = s390_gdb_arch_name;
512 
513     s390_cpu_model_class_register_props(oc);
514 }
515 
516 static const TypeInfo s390_cpu_type_info = {
517     .name = TYPE_S390_CPU,
518     .parent = TYPE_CPU,
519     .instance_size = sizeof(S390CPU),
520     .instance_init = s390_cpu_initfn,
521     .instance_finalize = s390_cpu_finalize,
522     .abstract = true,
523     .class_size = sizeof(S390CPUClass),
524     .class_init = s390_cpu_class_init,
525 };
526 
527 static void s390_cpu_register_types(void)
528 {
529     type_register_static(&s390_cpu_type_info);
530 }
531 
532 type_init(s390_cpu_register_types)
533